Basic Knowledge of Every Civil Engineer

CONCRETE GRADES:
M5 = 1:5:10

M7.5=1:4:8
M10= 1:3:6
M15= 1:2:4
M20= 1:1.5:3
M25= 1:1:2

CLEAR COVER TO MAIN REINFORCEMENT:
1.FOOTINGS : 50 mm
2.RAFT FOUNDATION.TOP : 50 mm
3.RAFT FOUNDATION.BOTTOM/SIDES : 75 mm
4.STRAP BEAM : 50 mm
5.GRADE SLAB : 20 mm
6.COLUMN : 40 mm
7.SHEAR WALL : 25 mm
8.BEAMS : 25 mm
9.SLABS : 15 mm
10.FLAT SLAB : 20 mm
11.STAIRCASE : 15 mm
12.RET. WALL : 20/ 25 mm on earth
13.WATER RETAINING STRUCTURES : 20/30 mm

WEIGHT OF ROD PER METER LENGTH:
DIA WEIGHT PER METER
6mm = 0.222Kg
8mm = 0.395 Kg
10mm = 0.616 Kg
12mm = 0.888 Kg
16mm = 1.578 Kg
20mm = 2.466 Kg
25mm = 3.853 Kg
32mm = 6.313 Kg
40mm = 9.865 Kg

1bag cement-50kg
1feet-0.3048m
1m-3.28ft
1sq.m-10.76sq.f t
1cu.m-35.31cu.ft
1acre-43560sq.ft
1hectare-2.47acre

DESIGN MIX:
M10 ( 1 : 3.92 : 5.62)
Cement : 210 Kg/ M 3
20 mm Jelly : 708 Kg/ M 3
12.5 mm Jelly : 472 Kg/ M 3
River sand : 823 Kg/ M 3
Total water : 185 Kg/ M 3
Fresh concrete density: 2398 Kg/M 3

M20 ( 1 : 2.48 : 3.55)
Cement : 320 Kg/ M 3
20 mm Jelly : 683 Kg/ M 3
12.5 mm Jelly : 455 Kg/ M 3
River sand : 794 Kg/ M 3
Total water : 176 Kg/ M 3
Admixture : 0.7%
Fresh concrete density: 2430 Kg/ M 3

M25 ( 1 : 2.28 : 3.27)
Cement : 340 Kg/ M 3
20 mm Jelly : 667 Kg/ M 3
12.5 mm Jelly : 445 Kg/ M 3
River sand : 775 Kg/ M 3
Total water : 185 Kg/ M 3
Admixture : 0.6%
Fresh concrete density: 2414 Kg/ M 3
Note: sand 775 + 2% moisture, Water185 -20.5 =
164 Liters,
Admixture = 0.5% is 100ml

M30 ( 1 : 2 : 2.87)
Cement : 380 Kg/ M 3
20 mm Jelly : 654 Kg/ M 3
12.5 mm Jelly : 436 Kg/ M 3
River sand : 760 Kg/ M 3
Total water : 187 Kg/ M 3
Admixture : 0.7%
Fresh concrete density: 2420 Kg/ M 3
Note: Sand = 760 Kg with 2% moisture
(170.80+15.20)

STANDARD CONVERSION FACTORS
INCH = 25.4 MILLIMETRE
FOOT = 0.3048 METRE
YARD = 0.9144 METRE
MILE = 1.6093 KILOMETER
ACRE = 0.4047 HECTARE
POUND = 0.4536 KILOGRAM
DEGREE FARENHEIT X 5/9 – 32 = DEGREE
CELSIUS
MILLIMETRE= 0.0394 INCH
METRE = 3.2808FOOT
METRE = 1.0936YARD

MATERIAL CALCULATION:
CEMENT IN BAGS
01. PCC 1:5:10 1440/5*0.45 129.60Kg 2.59
02. PCC 1:4:8(M 7.5) 1440/4*0.45 162.00Kg 3.24
03. PCC 1:2:4(M 15) 1440/2*0.45 324.00Kg 6.48
04. PCC 1:3:6(M 10) 1440/3*0.45 216.00Kg 4.32
05. RCC 1:2:4(M 15) 144/2*0.45 324.00Kg 6.48
06. RCC 1:1.5:3(M 20) 1440/1.5*0.45 32.00Kg 8.64
07. RCC 1:1:2(M 25) 370.00Kg 7.40
08. RCC M 30 410.00Kg 8.20
09. RCC M35 445.00Kg 8.90
10. RCC M40 480.00Kg 9.60
11. Damp Proof Course CM 1:3,20mm tk 1440/3*0.022 10.56Kg 0.21
12. 2"tk precast slab M15 324*0.05 16.20Kg 0.32
13. 3"tk precast slab M15 324*0.075 24.30Kg 0.49
14. GC Masonry CM 1:7 1440/7*0.34 70.00Kg1.40
15. Brick Work CM 1:6 1440/6*0.25 60.00Kg 1.20
16. Brick Work CM 1:4, 115tk 1440/4*0.25*0.115 10.35Kg 0.21
17. Grano Flooring CC 1:1.5:3 1440/1.5*0.45*0.05 21.60Kg 0.43
18. Plastering CM 1:3, 12mm tk 1440/3*0.014 6.72Kg 0.13
19. Wall Plastering CM 1:4, 12mm tk 1440/4*0.014 5.00Kg 0.10
20. Laying Pressed Tiles Over
a CM 1:4, 20mm tk 1440/4*0.022 7.92Kg 0.16

01. Any Concrete Work
(PCC, RCC) 0.45*35.315= 20.00
02. Damp Proof Course
CM `1:3, 20mm tk 1.00
03. 2"tk Precast slab M15 1.00
04. 3"tk Precast slab M15 1.50
05. SS Masonry in CM 1:7 15.00
06. Brick Work in CM 1:6 15.00
07. Brick Work in CM 1:4,115mm tk 2.00
08. Grano Flooring in CC 1:1.5:3 1.00
09. Plastering in CM 1:3, 12mm tk 1.00
10. Wall Plastering CM 1:4, 12mm tk 1.00
11. Laying Pressed Tiles over a CM 1:4, 20mm tk
1.00
12. Ceramic Tiles, Marble, Granite, Cuddapah slab
CM 1:4, 20mm tk 1.00

UNIT WEIGHT:
01. Concrete 25 kN/m3
02. Brick 19 kN/m3
03. Steel 7850 Kg/m3
04. Water 1000 Lt/m3
05. Cement 1440 Kg/m3
06. 1Gallon 3.78 Litres
07. Link 8" = 200mm
08. 1 Hectare 2.471 acr(10000m2)
09. 1 Acr 4046.82m2 = 100 cent

DEVELOPMENT LENGTH:
01. Compression 38d
02. Tension 47 & 60d
03. 1 Cent 435.60 Sft
04. 1 Meter 3.2808 ft
05. 1 M2 10.76 ft2
06. 1 Feet 0.3048m
07. 1 KN 100Kg
08. 1kN 1000N
09. 1 Ton 1000Kg = 10,000 N = 10 kN
10. 1 kG 9.81N

BRICK:
Weight = 3.17 - 3.80 Kg
Water absorption 12 to 15%
Compressive strength = 36Kn/cm2
230mm Wall/m3 = 460 Bricks + 20Cft Sand +
66Kg Cement